RWD 2.8 heads same as FWD?

[Alxsmt]

well at least the exhaust ports/bolt pattern on the ports? im thinking about picking up some headers for one and modifying them to fit my beretta

[smilinguy99]

Depends. If they are both iron heads, then they are for your purposes the same, but if you are talking about FWD aluminum heads, and RWD iron heads, then obviously the answer is one of these things is not like the other.

Hope that helps.

[Guest]

Agreed ^^^

The port spacing is the same. The bolt spacing is not, and requires at the very least the bolt hols to be slotted. This applies to genI/II comparisons, genIII is a whole new ball game, sharing the same bolt spacing as the genII, but a very different port shape.

[Alxsmt]

ok, thanks guys! one more question

so there would be a difference between the iron heads on my fiero compared to the 3500 aluminum heads? (as far as bolt pattern and port spacing) i was looking at them today and they seemed the same, but thats just by looking

BTW these are the headers im thinking about gettin to play around with. (waiting for an email back about what heads he has)

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&ih=018&sspagename=STRK%3AMEWA%3AIT&viewitem=&item=280106309271&rd=1,1

[Guest]

ok, thanks guys! one more question

so there would be a difference between the iron heads on my fiero compared to the 3500 aluminum heads? (as far as bolt pattern and port spacing) i was looking at them today and they seemed the same, but thats just by looking

BTW these are the headers im thinking about gettin to play around with. (waiting for an email back about what heads he has)
http://cgi.ebay.com/ebaymotors/ws/eB...6309271&rd=1,1

:O

No, they are QUITE different.

Honestly if you're going to build some headers, that require more than just a slight modification, from an existing set, it's MUCH easier to start with a box of bends and and some flanges, than to cut apart a set of headers.

[Superdave]

the port distance is the same but the bolt spacing is different (like allready said...)


When i built my first set of Longtube headers I used Iron head flanges on my old 3400 heads, the bolt holes had to be slotted like 1/8".

Pic:



But i agree with Raven, i built a front header for a V6 Jbody in around 2 hrs yesterday out of scrap U bends, i plan on finishing the rear and crossover tonight...

It's much easier to buy the round port flanges from "betterthanyou" on here and start from scratch. They fit the 3500 heads perfect, I'd stay away from the D port flanges. I don't care what anyone says, that's a pain in the ass and extra work for no reason.

[Alxsmt]

oh ok, i guess i wont get em then... i was thinkng about gettin some fiero headers and modifying them to fit he beretta too, but maby i will rethink that one too

[Guest]

What's so hard about using the D-port flanges?

With mine (made by my grandfather and the new batch is even better,being laser cut), All I have to do is line up the tubewhere I want it, tack it in place, use a little heat from a torch and using some persuasion, lay the tue into the corners of the D-shpae, and it is worth every effort to do so, anti-reversion is one huge reason why, better transition of flow from a D-shape port to a round tube, increasing flow, whihc is teh reason for building/adding headers is it not?

[Superdave]

I used D port ones on my longtubes, just seemed like extra work.


Here is the round port ones on a 3400 head...




I don't see that hurting flow at all. I guess it boils down to a personal preferance. I ended up using a small anvil setup to shape the tubes into the D at just the right angle so they'd slide in... I know some people have just welded the tubes to the outside of the flange as well.

[Alxsmt]

what size of tubing to u guys recomend for my beretta? (see sig for mods) and is there a way of measuring to make shure there equil length? i know if u measure one side on a pipe it will be longer than the other depending on the curves and stuff

also how much did the flange run ya?

[Superdave]

flanges are $50 cdn, damn good price.

I think they only come in 1 5/8" so unless you wanna spend time filling in gaps i'd just go with that.

1.5" would be ideal but 1 5/8" gives you room to grow.

for measuring i usually use a piece of wire or string and just follow the bends down the middle, straighten it out and measure that.. then just use the tape measure on all the straight sections.

Ideal tube length is around 28"-32" or so for longtubes.

[Alxsmt]

ok cool, thanks. if the header redesign doesnt come though on bstuff.com i will probly just make some

[geoffinbc]

My flanges fit 1 5/8" OD Tube. When I did a poll the concensus was 1 5/8" so thats what I went with.